Method of producing vacuum-lamps.



No. 814,794. PATENTED MAR. 13, 1906. D. MOP. MOORE. METHOD OF PRODUCING VACUUM LAMPS.

APPLICATION FILED APR. 21, 1904.

WWII/E8858; I INVENTOR fiMw/MF/Zr/m more.

ATTORNEYS DANIEL McFAR LAN MOORE, 0E, .NEWARK,

MOORE ELECTRICAL COMPANY TION OF. NEW YORK.

NEW JERSEY, ASSIGNOR To OF NEW YORK, N. Y.,A CORPORA- METHOD OF PRODUCING VACUUM-LAMPS.

Specification of Letters Patent.

Patented March 13, 1906.

Original application filed September 2, 1903, Serial No- 171,587.- Divided and this application filed April 21, 1904. Serial No. 204,173.

To all whom, it may concern.-

Be it known that I, DANIEL MCFARLAN MOORE, a citizen of'the United States, and a resident of Newark, in the county of Essex and State of New Jersey, have invented certain new and useful Improvements in Methods of Producing Vacuum-Lamps, of which the following is a specification.

My present invention relates to .an improved method of producing electricallyoperated gas or vapor tubes; and it consists more particularly in a method of manufac ture whereby a tube ma be produced having a contained materia of such character that it shall form a source of supply of or for regeneratin the gas which forms the source of light witIn'n the tube.

' My present application is-adivision of my prior application for 2, 1903, Serial No. 171,587, wherein Ihave set out certain advantages in respect to the life of the device, quality of light when the 'tube is em loyed as a source of ii ht, efficienc an other advantages whic are secure by the presence in the tube-or receptacle'of a suitable material comprising an electrolytically-treated organic substance, preferably one of which nitrogen is a constituent.

The special object of my invention is to secure t e presence of the desired material within the manufactured device by a simple and cheap method or process of manufacture.

To this end the invention consists, substantially, in applying to the interior of the tube or recepta e or to a section of tubing or receptacle employed in the manufacture of the device the particular or anic substance which is to be electrolytical y treated, then subjecting said tube or section of tubing to the action of the electric current and employing said tube or section of tubing with the converted material converted .upon the surfaces thereof as the tube or section of tubin for the completed device.

' y invention consists'also in a novel process: of producin a vacuum-tube lamp or similar vacuum-tn e" device with a' contained substance produced by electrolytic action upon an organic i'n'aterial, consisting in first 5 0 constructing the tube with 'the pro r amount of such substance contained wit 1 and thenexhausting the tube inthe usu 'al "mannertoproduce the desired degree of rarepatent filed September faction'of its contained gas and then finally sealing ofl'.

As stated in my priorapplication, electric tube-lamps and other devices having a contained gas or vapor and through the intc rior of which an electric current circulates are of comparatively short life, and in many cases where the device is used as a source of light the uality thereof is poor and the device is ine cient. This difficulty I have attempted to obviate by introducing chem- .icals'into the tube, which theoretically should be the source of fresh gas supplied as rapidly as the gas deteriorates under the action of the current, but at first met with only a measurable degree-of success, because apparently all chemicals, solid, .liquid, and gaseous, if of suitable quantity for the purpose act to chan rarefaction within the tube, since give off their gases too fast. The cipal object of the resent invention is to overcome this difficuiisy and to secure a manufactured lamp in which the vacuum shall be of the desired degree of rarefaction when the lamp is put into use and which shall ther after maintain asuitable de ee of rarefaction, as well as to secure ot er advantages herein referred to.

I have found that the difliculties heretofore they would experienced may be overcome by the introduction in any suitable manner Into the tube of anjorganic substance of an kind which p eviously to the sealin off oft e lain has been he m atosubjected to electro ytic action.

rial from which I have secured the best rcsults is obtained by subjecting an organic compound, animal or .vegetable, but preferably an aromatic hydrpcarbon-such as benzin, toluene, &c.or'a derivative thereof-- 'such as anisic, benzoic, (without nitrogen,)

hlppuric acid, and benzamid (with nitrogen)- t e ectrolytic action. While it is possible to form this material in ne tube or receptacle and remove it therefrom and place it in the manufactured tube or-receptacle, I prefer to secure its resence in the manufactured device in one 0ft efollowing ways: I take the length of tube or employed for the complete device and into the same I introduce the substance to lutreated, which in the case of a solid is preferably powdered and introduced into the tube form of receptacle such as is to be go the necessary degree of rin- and uniformly distributed over the interior tube fills with va or, which con enses on the cold walls, and t e t'ube becomes coated internally with the substance'employed in a finely-divided crystalline condition. If the substance is a liquid, I introduce a fixed amount and cover the walls of the tube with a thinfilm by rotating in a horizontal position. The tube is then sealed up, and being rovided with suitable ca s or electrodes by wl fich electric current of 'gh tension may be passed throu h the interior thereof is connected to a suitab e source of electricity and current passed-through the same, while at the same time, if desired, the air or other as is exhausted from the interior thereof, t e exhaustion of the air'or gas aiding somewhat in the celer-.

ity of the conversion of the material forming the coating upon the interior walls of the tube or otherwise existing therein. In some cases also decomposition of the material maybe hastened and aided by heating the tube,-

which ma be resorted to in the case when crystals o hippuric acid are employed, when ,it is found that even with the continued application of the current no apparent decomposing effect takes place and that the light in the tube instead of changing from a red color at the beginning of the operation to a thick white as the exhaustion progresses changes from a red to a very thin'white. In ordinary'cases near the commencement of the exhaustion the light inthe-tube-is adeep red color changing to a pure white, th1s change in color probably marking the fixation of the nitrogen and the production of an amid or other organic compound having nitrogen for one of its constituents. I also employ pure nitrogen in the place of air for this purpose.

By the above 0 eration there is produced ed solid residue forming coating upon the walls of the tube. The composition of this coating is uncertain, but in all preferred forms benzamid and in man 'cases acetainid is present in considerab e quantity. In the case of benzoic or anisic acid or other substance containing no nitrogen and similar hydrocarbons these amids are formed by the fixation of the nitrogen of the air in the tube while the current is travers' the tube.

In this operation the production 0 the coat-- ing seems to be assisted by lowering the res sure of the air or-other gas within t e tu e.

The same treatment maybe applied to a r of actions in which the substance already embracing nitrogen as a constituent for example, benzonitril, benzamid, acetamid, &c.

When the electrical treatment is applied to a substance originally containin mtrogen, the fixation of nitrogen by the eIectric current as set forth by the electrolytic action is of less importance.

While-1t is practicable to use any of the substances already mentioned in practice, I find it preferable to use the material roduced by electrolytically treating the a dehyde of anise known as aubepine.

. The tube or other rece tacle with the coating or material secured this process may then be used entirely as t e com lete manufactured device, although, an especially whenit is desired to secure illumination, the opaque nature of the coating on the interior 0 the tube is objectionable. Hence .I ordinarily prefer to use a section of tubing coated on its interior by the process described as a art of the tube of a complete or commercial amp or other device, and by preference also I use such section as the end portion of the tube, especially when, as is fre uen-tly the case, the said end section is provi ed w1th an external conducting layer of material, usually opaque, by means of which'the current is passed into and through the gaseous contents of the tube by electrostatic action; or, if desired, and especially when the complete tube is of very great length, a section of tubing having a coating produced upon its inner surface as already described may be inserted into and employed as a section of the tube forming the complete or commercial device. In this case it is desirable that the coating of material should be rather thick in order to supply a sufficient amount thereof to produce the results desired.

I The presence of the material produced. as described secures a smooth or perfectly steady uniform light,with an eflicient life for the tube several hundreds of times as long as a similar tube not having such new material within it. i

The action of the new substance and: the particular chemical constitution of the same resulting from the electric treatment described cannot be fully set forth; butaplparently the gases held b the solid materia are decomposed by the e ectric current and recombined .by the. catalytic action of the spon residue, and since this constantly and rapi y recurring action is nearly perfect the life of the tube is very great, being only limited by the slow breaking down or clogging of the porous residue, with a consequent loss of the necessary amount of surface exposed to regenerate the gases as fast as they are decomposed by the fcurrent-that is, this new material becomes the agent in a train or cycle ases forming the light are decomposed or a ected by the light- III ing current and transformed into a gas or gases whose chemical constitution is such that they can from the new substance or material be changed or recomposed into the gas which is effectlve in producing'the light. In some cases-as, for example, when variouslycolored tubes are required'it is desirable to use chemicals within the tubein accordance with any of the methods herein described and introduce also into the tube various gases, either singly or in mixture, and I have found that the presence-of the chemical causes such gases to last many hundreds of times longer. V

By first treating the substance to be employed in the lamp or tube by electrolytic action .until it is decomposed to its final form and exhausting the tube with the contained material to the required degree or to secure the desired va or or gas densit ing light the ifiiculties-hereto ore met with in this class of devices are obviated to a' considerable. extent-namely, the difficulty that the chemical or material, solid, li uid or gaseous, when employed directly in and decomposed by the action of the electric current when the lamp is in use and form.

objectionablespots or discolorations depos ited on the inner walls thereof along the lightgiving area. It-is obviously, therefore, possible in order-to secure this result to remove the coating secured in themanner already herein-described from the interior wall of the tube and introduce it into the tube to be used as the light-tube; after which the lattermay be scaled up and exhausted in the ordinary way to produce the required density of contained gas or vapor.

manufacturing tubes for lighting and have set forth the use of external electrodes or caps therefor, I do not wish to limit myself" to this class of tubes, since the invention is elgually a plicable for the'productoin of long 1' e in al classes of vacuum-tubes by maintaining the vacuum at a stable degree of rarefaction, it being understood that this includes X-rag tubes and light-tubes, either with interna or external electrodes. I

.Another great advantage of the use of chemicals as described is that acomparatively low vacuum can be used, and et the light is'satisfactory in all res ects. eretofore in order to obtain such a ight a high vacuum, comparatively speaking, was. absolutel essential, and therefore required suitab e vacuum-pumps for the roduction of the high vacua, and this involved the use of mercurypumps; but with the chemicals as described the tubes can be exhausted by using only socalled mechanical pumps-that is, various kinds of vacuum-pumps that do not em.

ploy mercury. In the descri ing these chemicals I have stated that a vacuvacuum pump attached to it.

have found that this latter for pro'duc-' ght tubes spon t e p ate or wall of glass, extending in some cases for several 'inches beyond the point .at 3, which terminal is rovided with a suitption of the method of prepar um-pump is attached to the tube containing the chemical which is being acted upon by high-tension electricity; but I do not wish to limit myself to the use of the vacuum as a necessary factor, since the material may be prepared by spreading the carbon compound or other chemical on a plate of glass and then assing the electrolyzin -current through it by placing one-termina of the high-tension source of electricity beneath the plate and another above it and close to the film or layer of material. This causes high-tension sparks to radiateall over and through the chemical, causin part of it to evaporate and after some time leaving the residue in the form of a coatin on the plate that is similar to that produce within the tube which hasa high- However, I method is far more laborious, more expensive, .and not nearly as preferable as the vacuum process.

The material produced in the" above-(lescribed way will generally be in the form of a fixed solid residue forming a more or less but still firmly adherent coating upon of-application of the current or electrolyzin agent. When desired, it ma be remove from the surfaces to which 1t adheres by scraping it off, or it may bewashed off by the use of various liquids and then recovered by eva oration.

In t e accompanying drawings, Figure 1 shows a tubeorreceptacle that may be employed-inproducing the substance and at' the same'time be a part of theJight-tube. Fig. 2 .shows a tube specially designed for preparing Although I have described the manner of the chemical. Fig. 3 shows a tube for;.introducing the chemical in a 'modified way. Fig.

I05 4 shows a modified form of apparatus that .ma be used folizproducing the substance.

efen'ing to 1g. 1, the terminal of atube of translucent material, like glass, is indicated 1 IO able conducting-cap ike, for instance, a coating of plumbago.provided with an attached conductor 8, by means of which electric energy may be supplied electrostatic-'v 1 ally to the contents of the tube. 4is a small tube attached to the larger receptacle for the purpose of permittin the receptacle to be r i exhausted by the app cation of a as-pump The bodyof the receptacle of trans ucent material is indicated at 5. It will be'understood that the opposite end of the tube is provided with a similar ea or terminal (either inside or outside.) T e substance to I. be treated havin been introduced into the tube in either of t e manners described or in'i fz5 any other suitable manner, preferably by s reading it over-the. interior surface b s aking the tube, said tube may then bea lowed to drain off if the material introduced is of liquid form, after which it is proper] y 1 0 sealed and the electric current applied, the exhaustion of the air or other gas .present in the tube at such time being carried on, preferably, during the application of the current. After the completion of the process, which will be indicated in the manner already described, the tube may be cut and the material recovered therefrom, as already set forth. The material will then be collected, if the tube is of considerable length, near the points of application of the current and under the cap,

the coating extending, however, slightly beyond the gap into the translucent portion of the-tube. The material removed may then be introduced into another tube to be used as a completed device and said latter tube exhausted during the application of the current until the desired degree of exhaustion is obtained, as indicated by the color of the light, or, if desired, the presence of the sub stance in the tube having been secured as already describedit may then be allowed to remain and the tube itself employed as the operating device, it bein understood, however, that this is generally a desirable procedure only when the tube is of such length that the opaque or slightly-o aque coating does not extend very far into t e translucent portion. In general the completion of the process will be indicated by the changed appearance of the coating in the translucent parts where said coating exists, such change being generally a change of color to a brown color. The material removed Will appear as a granular sawdust-like substance somewhat resemblin brown sugar in appearance, but readily re need by attrition to an almost impalpable powder that also sometimes has a chocolate color.

As indicated in Fig. 2, the material may be manufactured in a tube or receptacle of comparatively short lengthhaving a translucent section 2, in which a coating of the material on the inner walls may be secured in the manhaving been sealedin place to make a part of the:complete device, the manufacture of the same maybe completed by exhaustion of the contents to the desired degree of rarefaction in the proper manner either with or without the simultaneous application of the electric current.

In Fig. 3, 6 indicates a separate receptacle in which the substance to be treated may be placed, so that'when heated its vaporswill pass into and condense on the walls of 7, the exterior of which is coated with graphite or other suitable material, which is connected with the wire 8, leading to a source of electricity of suitable potential.

In Fig. 4, 9 indicates a plate u on which the substance 10 to be treated ma be s read, and 11 and '12 the electrodes for el said material in one of the manners previously mentionedviz., in the open air.

In the foregoing specification and annexed claims the term tube is used as s nonymous with a sealed receptacle of any orm or contour.

, My invention is not limited to tubes containing only a rarefied gas acting and acted upon as herein described, but may be used with tubes in which there is also a mercuryvapor or other metallic or mineral vapor or An electrically-operated tube in whic a material produced by electrolytically treating an organicv substance is employed is not claimed herein, but forms the subject of claims in my rior application for patent hereinbefore refined to. I

While I have found that all organic compounds, especially those of the hydrocarbon class, will be suitable for increasing the life of a vacuum-tube as above described, those organic compounds which come under the head of benzene derivatives have a decided advantage over others. About seventy-five per cent. of all organic compounds come under this headthat is, they do not belong to the aliphatic class, whichis composed rincipally of such compounds as beeswax, utter, lard,

ectro yzing- &c., the carbon chains of which can be readily broken up; but the residues from benzene-dcrivatives have the highest melting and boiling pointsof any organic compounds, (not metallic com ounds,)..and thisiindestructible feature of t e benzene derivatives is that they all have six (6) carbon atoms permanently linked together inrings.

What I claim as my invention is- 1. The herein-described method of manufacturing electrically operated vacuumtubes, consisting in coating the interior of a tube or receptacle of any desired form adapted for use in the completed device with an organic substance, electrolyzing said substance to form an adherent coating ,of an electrolytically-produced substance upon the 'interior of the receptacle or tube and utilizing said tube as a tube or section of tubein the complete device.

2. The herein-described method of manufacturing electric lights in which the lightgiving source is a rarefied gas, consisting in treating an organic substance contained in a section of the tube or lamp by an electrolyt c process, producing thereby a fixed sohd resi-. due forming an adherent coating upontl e wall of the tube and utilizing said section for a section of the complete lamp and then exhausting the latter in the ordinary way.

3. The herein-described method of manufacturing electric lights in which the lightgiving source is a rarefied gas, consisting in treating an organic substance contained 1n a section of the tube orlamp by an electrolytic process with the application of external heat,

e the previously electroand producing thereby a fixed solid residue formmg an adherent coating upon the Wall of the tube and utilizing said section for a section of the complete lamp and exhausting the latter in the ordinary way. 4. The herein-described method of producing vacuum-tubes for electric lighting consisting in coating the interior of a glass receptacle with a liquid hydrocarbon, passmg an electric current through said receptacle while at the same time exhausting air gas from the tube, producing thereby a fixed solid residue forming an adherent coating upon the wall of'the tube and utilizing sald'rece tacle as a section or portion of another'tu e or receptacle designed for employment as a complete lamp and exhaustmg the latter in the ordinary way.

5. The herein-described method of manufacturing vacuum-tube lamps'containing a material designed to form a source of gassupply during operation of the lamp, consistmg' m first subjecting van orgamc substance to electrolytic action, exhausting the lamp and subsequently and while the electrolytically-treated substance is contained therein sealing ofi the lam 6. The herein-describe method of producing vacuum-tube lamps without spots or discolorations arising from the decom osing substance, consisting in first electrolyzing an organic substance designed to form a source operation of the lamp ofl the lamp after ex-' haustion and whi lytically decomposed substance is contained therein.

7. The method of producing vaclium-tube lamps with a stable vacuum and with a contained material designed toform a source of gas-supply during operation of the lamp, consisting in introducing an organic substance into the lam passing an electric current through the amp to decompose such subistance and at the same time exhausting the am tica ly completed, sea ing the lamp 011'.

8. 'The herein-described method of securing a stable vacuum in vacuum-tube lamps containing an electrolyzed organic su stance, consisting in first subjecting such substance to electrolytic action to completely decompose it, and applying the exhaustpump, and finally seahng-ofi'. I

9. The method of producing Vacuum-tube lamps with stable vacuum and witha contained material, adapted to maintain the desired degree of rarefaction, consisting in reducing an organic material by electrolytic action to its final form and sealing off the lam after exhaustion to the degree of rarefaction desired for commercial operation.

10. The herein-described method of manu facturing vacuum-tube lamps, containing a substance designed to form the-source of gas durin operation of the lamp, consisting in intro uclng an organic substance into the lam passin an electric current through the lamp to ecompose the substance to 1ts final form while at the same time'exhausting the lam and finally sealing ofl.

1 1. he herein-described method of manufacturing vacuum-tube lamps containing electrolytically treated aubepine forming during operation of the lamp a source of a gas by which the desired degree of rarefaction and luminosity is maintamed, consisting in first subjecting the aube ine to the action of an electric current by w duced to its final form and sealin off the lamp while it contains the comp etely-re duced aubepine'and subsequently to the exhaustion of the tube to secure the desired degree of rarefaction of its gaseous contents.

and after decom osition has been prac-' 'ch it may be re- Signed at New York, in the county of New i York and State of New York, this 4th day of March, A. D. 1904.

. DANIEL MOFA L N MOORE.

Witnesses: C. F. TISOBNER, Jr.,

Jo ANNA B. TALLMAN. 

